Patent GB-248806-A (GB)
Title: Improvements in or connected with sound reproducing machines
IPC: G11B17/00
Filed: 1924-10-11
Abstract: 248,806. Robimarga, L. Oct. 11, 1924. Multiple machines. - Relates to multiple - turntable soundreproducing machines in which a continuously rotating shaft is successively and temporarily clutched to two spindles geared to the turntables in such a manner that when the playing of a record is completed the turntable carrying it is stopped and another comes into operation immediately. A machine constructed according to the invention comprises a pair of shafts geared to the respective turntables, these shafts being axially aligned with and on either side of the continuously rotating shaft, spring- operated means for connecting one or other of the auxiliary shafts to the driving shaft, and means for automatically changing over the drive at predetermined times. In the machine shown, a shaft 8 driven by an electromotor (not shown) carries two discs 15', 15" respectively adjacent to discs 11', 11<11> on shafts 13', 13", which drive through bevel-gearing 18, 19 the turntable spindles 20<1>, 20". The discs 11<1>, 11" carry pivoted clutching pawls or catches 16<1>, 16<11>, which are adapted to drive the discs 11<1>, 11<11> when they engage in notches in the discs 15<1>, 15". Each of the spindles 20<1>, 20<11> is geared to a centrifugal governor, and each may also drive an additional turntable spindle by means of chain gearing. Spindles 29', 29<11> are driven by worm gearing from the shafts 13', 13<11>, and each carries a graduated noched disc 32<1> or 32", upon which bear the ends of spring-pressed members 39<1>, 39<11>. These control the position of a slidable bar 41, which carries pairs of projections 45<1>, 45" adapted to act upon the pivoted catches 16<1>, 16". The arrangement is such that when the end of one member 39<1> or 39<11> snaps into the notch of the corresponding disc 32<1> or 32" the bar 41 is moved so that one of the pairs of projections 45<1>, 45" effects the disengagement of the adjacent catch 16<1> or 16" from its driving disc 15' or 15", whilst the other catch is allowed to couple to the main shaft the auxiliary shaft which has been stationary during the preceding period. Thus the change-over from one turntable to another is effected, and the record that has just been played may be removed from the now stationary turntable and replaced by another. The graduations on the discs 32<1>, 32<11> correspond to revolutions of the respective turntable, and when a record has been placed in readiness for playing, the disc 32<1> or 32" is set so that the end of the associated member 39<1> or 39<11> rests against the graduation showing the number of revolutions required for that particular record, as indicated by a number marked on it. The shafts 13<1>, 13" also carry graduated discs 30<1>, 30<11>, which move past fixed pointers and show at any instant the number of rotations which a record has to make before the completion of its playing. When the machine is employed in conjunction with a kinematograph, each of the shafts 13<1>, 13<11> carries a cam 26<1>, 26" which operate switches 44<1>, 44<11> controlling a device for maintaining synchronism between the two machines.